ZWZ Reaches New Milestone in Spherical Roller Bearings Through 87 Years of Expertise

In the precision systems of industrial manufacturing, bearings are like the "joints of machinery," and their performance and quality directly determine the operating efficiency and stability of the entire mechanical system. Among the many types of bearings, stamped cage self-aligning roller bearings, with their unique structural design and excellent performance, have become the preferred product for heavy-duty, high-speed equipment.

From Bearing Veteran to Industry Benchmark: A Legacy of Quality

ZWZ's history dates back to 1938. In September 1949, the first domestically produced industrial bearing was born at Wafangdian Ball Bearing Factory, a significant contribution to the founding of the People's Republic of China. During its arduous pioneering period from 1950 to 1978, it underwent the relocation of its southern factory to the north, eventually becoming what is now Harbin Bearing, assisting in the construction of Luoyang Bearing during the First Five-Year Plan, and undertaking the construction of Xi'an Bearing during the Third Front construction. Historically, ZWZ has supported and provided thousands of talents to various bearing enterprises, and the Chinese bearing industry flourished from here, earning it the reputation of being the "cradle of China's bearing industry."

After the reform and opening up, ZWZ established a modern enterprise system in 1995, transforming from a factory system to a company system. In 1997, ZWZ was officially listed on the Shenzhen Stock Exchange. In 2024, ZWZ and Dalian Heavy Industry Equipment Group underwent restructuring and integration. It can be said that the history of ZWZ is a history of the development of China's bearing industry.

"After the restructuring, the company's value creation capabilities, market competitiveness, and brand influence have significantly improved," remarked Meng Wei, Party Secretary and Chairman of ZWZ, in an interview. This large state-owned enterprise, with bearing manufacturing as its core business, has undergone 87 years of refinement and transformation, developing into an industry benchmark with 647 patents and leading the formulation of 2 national standards and 4 industry standards. Every important milestone in its development reflects its unwavering pursuit of technological innovation.

"We have always adhered to independent research and development, investing 6% of our annual revenue in R&D," explained Luo Guibin, Deputy General Manager of Wafangdian Precision Spherical Roller Bearing (Wafangdian) Co., Ltd., a subsidiary of ZWZ, pointing to various patent certificates in the company's exhibition hall. These patents cover multiple fields such as bearing design, manufacturing processes, and material applications, including many core technologies with international leading levels. "Patents have not only improved our technological level but also given Chinese bearings a voice in the international market," Luo Guibin proudly stated. ZWZ has also established national-level engineering technology centers, postdoctoral research workstations, and other innovation platforms, forming a complete innovation system from basic research to application development.

From Raw Material Selection to Finished Product Traceability: Striving for Excellence Across the Entire Chain

In bearing manufacturing, the selection of raw materials is fundamental to determining product performance and lifespan. ZWZ has established strict standards for steel procurement. Selected materials must possess high strength, high hardness, and excellent wear resistance. Each batch undergoes chemical composition and mechanical property testing before warehousing. For this purpose, significant investment has been made in advanced equipment such as German-made spectrometers and electronic universal testing machines. The spectrometer can accurately detect the chemical composition of steel within 3 minutes, with a detection accuracy of 0.001%. The electronic universal testing machine can simulate actual bearing operating conditions, conducting tensile, compressive, and bending mechanical property tests on the steel. These devices ensure stable and reliable material quality. ZWZ has also established a raw material traceability system. Each batch of steel has a unique identifier, allowing traceability of its origin, production date, inspection report, and other information.

"In terms of manufacturing processes, ZWZ continuously innovates, for example, by adopting bainitic heat treatment quenching technology," explained the head of ZWZ's technology R&D department. "This technology, through isothermal transformation within a specific temperature range, significantly improves the hardness and wear resistance of the material while maintaining its original rigidity." Grinding is one of the most precision-required processes in bearing manufacturing. ZWZ has introduced high-precision CNC grinding machines from Germany, achieving a machining accuracy of 0.001mm, equivalent to 1/100th the thickness of a human hair. The fully automated CNC grinding machines in the workshop can simultaneously grind both the inner and outer surfaces of the bearing outer ring, increasing efficiency by three times compared to traditional equipment.

In the finished product inspection stage, ZWZ uses an advanced bearing performance testing platform to comprehensively test the bearing's rotational flexibility, lifespan, noise, vibration, and temperature rise by simulating actual bearing operating conditions.

ZWZ has also established an assembly quality traceability system. Each assembled bearing has a unique identifier, allowing traceability of its assembly process and the quality inspection results of each step.

From Independent Design to Widespread Application: A Masterpiece

As the third-generation self-aligning roller bearing developed by ZWZ, the stamped cage type self-aligning roller bearing, awarded the "Liaoning Excellent Product" title in 2025, adopts a structural design of "stamped cage + movable spacer". This innovative design increases the number and length of rollers, optimizes lubrication distribution, and gives the bearing advantages such as higher load capacity, wider speed range, longer service life, and lower operating noise. The rated dynamic load and rated static load of this bearing are both more than 20% higher than traditional self-aligning roller bearings, the maximum speed can reach 1.5 times that of traditional self-aligning roller bearings, fatigue life is extended by more than 30%, and noise level is reduced by more than 5 decibels.

Currently, stamped cage type self-aligning roller bearings are widely used in heavy-duty, high-speed, and high-precision transmission equipment. In the steel and metallurgical industry, this series of bearings is used in equipment such as rolling mills and continuous casting machines to withstand high-temperature radiation and impact loads; in the mining machinery field, this series of bearings is used in equipment such as crushers and vibrating screens to cope with high dust and strong vibration conditions; in the port and engineering machinery field, this series of bearings is used in equipment such as hoists and large cranes to ensure the safe and stable operation of the equipment.

Today, ZWZ's stamped cage type self-aligning roller bearings have won widespread recognition from customers both domestically and internationally for their superior performance and reliable quality. "Our products are very popular in overseas markets, especially in the European wind power sector, where we have become the preferred supplier for many Fortune 500 companies," said the head of overseas sales at ZWZ with pride.

With the continuous expansion of the international market, ZWZ's influence in the global bearing industry is growing stronger. The company actively participates in the formulation of international standards, holds important positions on international bearing standards technical committees, and has made significant contributions to enhancing the competitiveness of Chinese bearings in the international market.